To expand; if d<=0.19, to detect this effect at p<0.05 with 75% odds, we need ~75 pairs of nights or ~150 nights of data:
pwr.t.test(d=(456.4783 - (456.4783 - 17.32))/131.4656,power=0.5,sig.level=0.05,type="paired",alternative="greater") n = 75.44403 d = 0.1911111
Doable, but not trivial.
To expand; if d<=0.19, to detect this effect at p<0.05 with 75% odds, we need ~75 pairs of nights or ~150 nights of data:
Doable, but not trivial.